1. Field of the Invention
The invention relates to hoses and a method for manufacturing the same, and in particular to a hose suitable for heavy-duty applications yet having improved flexibility. More particularly, the present invention is directed to a hose having a corrugated exterior surface containing a single wire lead at least partially surrounded by a tapered rubber profile that facilitates flexibility and easy handling of the hose but is capable of withstanding the wear and tear encountered during the intended uses of the hose.
2. Background Art
Typically, the purpose of a hose is to provide a flexible connector or conduit between two points. In the past, there have been many attempts to manufacture a hose that is both flexible and that possesses the necessary strength to meet the specifications of a given application. However, these two requirements of flexibility and strength often conflict. More particularly, making the hose strong enough using conventional manufacturing technology conflicts with the desire to make the hose as flexible as possible. Flexibility is desirable for workers to make their handling and use of the hose easier, less fatiguing, less time-consuming in its application, and more convenient. In most applications where such flexibility is required, some part of the hose strength must be compromised. Where this sacrifice cannot be accommodated, the hose must be stiffer with the previously mentioned problems posed by the non-flexibility that comes with such stiffness.
Heretofore, hoses designed to be flexible conventionally have been made with a double wire lead. More specifically, two wires are wound around the exterior surface of the hose in a spaced-apart, parallel and helical fashion. Alternating spaces between the wires then are filled with a section of rubber, and over-wrapped with a layer of rubber that becomes the hose cover. Prior to the hose being cured, it is wrapped with a helically wound overlapping strip of cure tape, usually made of nylon, so that it will shrink during the cure to consolidate the hose layers. Following this overwrap of the cure tape, but prior to the hose being cured, a rope, which normally also will shrink during the cure, is wound around the hose between the wires in the spaces that have not been filled with the previously mentioned filling rubber.
This method of manufacture will produce the desired alternating ridges and valleys or corrugation seen in hoses made to be more flexible than hoses made with smooth exterior surfaces. Typically, the difference in height between the top of each raised rubber ridge to the bottom of each valley where the rope is placed is normally less than the overall thickness of the hose wall as measured from the bottom of the valley where the rope is placed to the interior surface of the hose. Therefore, when the hose is bent, the flexing takes place between the alternating wires and the rope valleys. However, because only every other valley can compress, the flexibility of the hose is reduced.
The present invention solves a long-felt need in the art by providing a novel flexible hose construction and process of manufacture that will provide the required strength to meet the needs of a given application while also being extremely flexible for ease of handling. This unexpected result is achieved through a hose structure manufactured with a single helically-wound wire covered with a tapered rubber profile, and wherein the height of the tapered rubber profile is greater than the thickness of the hose tube wall.
Objectives of the present invention include providing and manufacturing a relatively flexible hose that is easy to handle, but which is capable of withstanding the wear and tear encountered during heavy-duty use of the hose.
Another objective of the present invention is to provide such a flexible hose that generally is free of kinking or collapse when it is bent.
A further objective of the present invention is to provide such a flexible hose which is relatively inexpensive and lightweight, yet durable.
These objectives and advantages are obtained by the flexible hose and method of manufacture of the present invention, the general nature of which may be stated as including a flexible hose comprising a hose tube having an exterior surface, a single wire helically wrapped about the hose tube, an elastomeric ridge at least partially encasing the wire, the elastomeric ridge forming alternating ridges and valleys on the hose tube exterior surface.